I purchased this for my SO to use with her daycare kids, but also as a bit of nostalgia. I had a similar (but smaller) set as a kid. I figured for under $50 with that many pieces it would be worth a shot.I am very impressed! Not only is the construction very sturdy, but the included parts make for an absolute blast! I built it in my work office, and had an afternoon with coworkers feeling five again! The pieces are nicely laid out in bags and, are very sturdy to fit together! I was concerned about quality (for the price especially) but I am very impressed! Even the "water wheels" seem like they will hold up for a while. There are so many different things you can do with this set, it's almost a never-ending story....the best part is that it even fits with the pieces from my old set that is probably 25 years old!No cons here, hours and hours of fun while also being a great learning tool, building tool, and great for both gross and fine motor skills! I would suggest using some real marbles though, they are quite a bit more fun than the plastic 2-piece ones they include...although it sure is fun to see 60 marbles running through your creation!